From shortly after World War II until 1991, the U.S. and the Soviet Union were the two main powers engaged in the Cold War. Now, a lot of experts and analysts have talked about the current tensions between the U.S. and Russia, which was the largest part of the Soviet Union, and these observers have used the term new Cold War to describe what could happen again.
But with such dramatic changes in technology between 1991 and now, a modern day Cold War could look vastly different from the one in your history books. For one thing, not all of the weapons that the nations have today are even visible.
SUBTITLE: The Cold War, then and now.
RACHEL CRANE, CNN CORRESPONDENT: The Cold War was a conflict between two nuclear super powers, West versus East, capitalism versus communism, a high stakes chess match.
The first question is, what`s temperature have to do with war?
Well, Hot Wars involve battles and all peace talks have stalled.
Warm Wars have negotiations. Armies are mobilized, though there`s still a chance for peace.
But with the Cold War, neither side was in direct conflict. Nuclear weapons made both countries reluctant to fight. Instead, they fought through proxy war and espionage, and for 45 years, the threat of nuclear war loomed over the world. The conflict ended with the collapse of the Soviet Union in 1991.
The question is, are we on the verge of the Second World War?
Today, tensions between the U.S. and Russia have reignited. Flash points like Syria, the annexation of Crimea, and suspicions of state-sponsored hacking have some observers fearing we are already in a new Cold War.
Both countries are tied to a string of international conflicts. But digital warfare has become a vast new battlefield. Cyber espionage is cheap, hard to trace and presents real economic and security fears. It is evolving quickly, as states rely more on digital networks.
The U.S. and Russia still have huge nuclear arsenals and military might, but digital information may be the most coveted new piece on the chess board.